Code point
U+2554
Glyph appearance depends on your fonts.
U+2554
SoU+2554 BOX DRAWINGS DOUBLE DOWN AND RIGHT is a Unicode 16.0.0 character in the Other Symbol category. It belongs to the Box Drawing block.
Choose the representation you need, then copy its value.
U+2554
9556
╔
╔
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E2 95 94
2554
00002554
%E2%95%94
\u2554
\u2554
\u2554
\2554